


Faerie Lights 'N' Lacy Lingerie

by mabelsguidetolove



Category: Gravity Falls
Genre: F/M, First Time, Older Characters, Smut, Twincest, atmospheric bangin', pinecest - Freeform, pinescest - Freeform, treehouse sex
Language: English
Status: Completed
Published: 2016-02-21
Updated: 2016-02-21
Packaged: 2018-05-22 09:32:27
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,629
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6074128
Author URL: https://archiveofourown.org/users/mabelsguidetolove/pseuds/mabelsguidetolove
Summary: <blockquote class="userstuff">
              <p>A (better) sequel to Bodies Change. After Dipper, ahem, services Mabel, she feels obliged to return the favor about a billion fold. Why? Mostly because she's a showoff.</p>
            </blockquote>





	Faerie Lights 'N' Lacy Lingerie

A couple of days after the incident with Mabel in the bathtub, Dipper was finally beginning to accept… Well, that he casually gave his twin sister oral. I mean, he wouldn’t put it that way if he said it out loud (nor was he ever going to mention it to anyone in the first place), but that is definitely, definitely what he did.

Anyway, moving on. It was a lovely autumn evening and the sun was already set when dipper got a text.

> _‘meet me in the treehouse ;P’_

Ah. Of course it was from Mabel. He didn’t take the time to reply since they were on the same property at the time, instead taking the opportunity to step into the backyard to see what she had planned.

Squinting up at the sunset-backed juniper fixture, he couldn’t really tell if she was even inside. Although there was a peculiar, slightly dim glow coming from within. So he sighed, climbed up the ladder, and hoped for the best.

“Hey there, bro! You finally made it!”

_**“M-Mabel?!”** _

His jaw dropped instantly. The treehouse was filled with strings of lights, there was a sudden addition of pretty red curtains, and there were a bunch of pillows stacked in the middle. Meanwhile, songs from a punkish seventies band he really liked were playing on her pink laptop in the corner. But that wasn’t all. On top of said pillows was a confidently kneeling Mabel in a lacy mint and white balconette bra, a matching frilly garter belt, a lace collar with a bell on it, and… Nothing else.

_Way to overdo it, sis._

“Yeah. What, are you surprised?” She shrugged, smiling as innocently at him as she would have if she were fully clothed.

“A little, actually. I mean, this is some insanely amazing decoration, and…” He noted the absence of a previously present mass of downy curls of hair below the waist. “Did you shave your _entire body_  from the neck down for me?”

“What can I say? Beauty hurts. Also, I read on the internet that it makes you more sensitive or something.”

“Fair enough. But I’ve gotta ask: where the heck did you get that sexy lingerie?”

“Internet. Also, remember?” She tingled the small silver cat bell on her choker necklace. “I made _this_ when Professor Choconibs died.”

“Oh, yeah. It always sort of freaked me out. Like, what if it’s haunted or something?”

“Pssh, _whatever,_ ” Mabel scoffed, beaming a grin while rolling her eyes. “Like the Professor would be all, ‘gimme back that bell i don’t need anymooooore, _ooooooh’_. Anyway, I did say I was gonna pay you back. And I’m planning to do it twofold, you know what I mean? ”

“Hold up,” Dipper murmured. “All of this is you… ‘Paying me back?’”

“Yup!”

“You don’t owe me anything, though…”

“I know that. That’s just what makes me so nice.”

“And this is, like, super ultra extravagant…” Dipper commented incredulously, touching the soft translucent curtains with his hands, smirking. “But I shouldn’t expect anything less from the ever-frivolous Lady Mabelton, right?”

“You got it, Sir Dippingsauce!”

“So, uh… Want me to take off my pants or whatever?” He said after a period of awkward silence, the two staring at each other in an embarrassingly ravenous state.

“Take it all off, dude! I want the Full Monty!” She exclaimed as if she thought he’d never ask.

“Good choice, madame,” he laughed as he began to do so. Mabel sure was a girl who knew what she wanted, and this situation posed no exception. “I’m still pretty sure I look better with clothes on, though.”

“No way, bro-bro. You’re like a freaking Adonis…” She touched an index finger to his stomach and trailed it downwards, causing him to blush. She giggled at the face he was making. “But maybe with more hair. Like, a lot more hair.”

“Y’know,” he chuckled, changing the subject. “If I’m gonna be fully exposed like this, you probably should be too. Take off the underwear, it’s so frilly that it kind of makes you look like a wedding cake.”

“A _sexy_ wedding cake?”

“Yes. A _sexy_ wedding cake. But it would get in the way of our bodies or whatever, and I don’t want to ruin your nice clothes.”

“Well, then, Mister Big Stuff,” she huffed, crawling towards Dipper, a mischievous grin spreading across her face. Her gaze sent shivers down his spine as they locked eyes, and he knew exactly what she was going to request of him.

“Do it for me, then.”

Her lips crashed into his, gravitating him towards her almost immediately. He reached his hands around her, trying to find the hooks in the back.

“It’s a front clasp, dorkus,” she whispered between kisses, and she proceeded to do it herself, only letting him slide the garment off her arms and toss it to the side.

After a few more minutes of awkward fumbling on Dipper’s part, her body was finally free from any encumbering clothing items. Mabel guided her brother to a lying position on the floor, situated herself over his hips and started to lower her own.

“Oh shit. _Waitwaitwait!_ ” He stammered at the last minute, pulling away and reaching his hand towards his discarded pants as he pulled a small foil square out of the pocket, handing it to her.

“Oh, yeah! Good thing you remembered, ‘cause I sure didn’t.” 

"Wow, uh, be careful with that kinda thing. In the future, I mean," he murmured; she held the small rubber circle to her own crotch whilst once again lowering herself onto Dipper as she began to feel him inside her; she knew that wasn’t the way health class had taught them to do it, but she was sort of hot and bothered at this point, and therefore in a bit of a hurry.

And damn, were they both glad for that in the end.

“Augh, _f—fuck,_ Mabel,” Dipper grunted as his manhood plunged into her, slowly but surely gaining rhythm as he grabbed ahold of her behind and began to thrust.

“Nngh, Dip. That hurts…” She quivered.

“Oh, should we stop?” He panted, barely able to form the words. “Should I slow down?”

“No… Keep going. It feels kinda n… _Ahh…_ ”

 _Got it,_ he thought to himself, continuing to gyrate, all while kneading her soft, flushed peachy skin with his fingers, making every appendage count. In response, Mabel dug her short amethyst-painted nails into his chest, adding just a lovely dash of pain to this cocktail of unbridled pleasure. She was far wetter at this point than she had been before; they still knew it was wrong, but somehow that made everything they were doing feel even better.

“Mmm, Mabel,” Dipper moaned in an unexpectedly low growl. And it was music to her ears; she loved the way it rolled off his tongue as he winced at her, the way his voice sounded, the fact that it was her name that he was saying. Even the way his voice seemed to quake. It made her tighten up around him as her face turned a lovely shade of pink.

 _“Ohmygosh,_ s-say it again,” she said, her voice trembling as she felt her whole body warm up. Meanwhile, her brother’s thrusts became more deepened and elongated, filling her in completely.

 _“Mabel…!”_ As he shouted her name once more, he felt his cock twitch. Looks like he’s reached his threshold. His grip on her intensified and her nails came this much closer to breaking his skin as a strange sensation went through the both of their bodies, causing them to feel each other shiver. Afterwards, they rolled over and quickly collapsed into a heap of sweat and heat on top of the mountain of pillows.

“That was… _Phew_. Wowie zowie.” Mabel exhaled, gazing into her brother’s shining brown eyes. He gazed back, and the both of them felt a residual energy being passed back and forth.

“Couldn’t have said it better mself,” he sighed. “But, uh—”

“The twin thing? You should’ve thought about that before you stuck your peen inside me,” she said mockingly. “Or, you know, fallen in love with me. Wiiiink.”

“Can’t argue with that… But man, you just look so... Damn beautiful in this light,” he mused as he touched a hand to her face in an act of careful tenderness. “I really can’t help myself around you, Mabes. It’s sort of a problem.”

“Pfft, _yeah._ I am such a bad influence, aren’t I?” She laughed, inching her body closer to Dipper’s, pressing her chest against his and wrapping her arms around his neck.

“Well, duh. Look at you right now,” he snarked, glancing down.

“My eyes are up here!” she said, ruffling her sibling’s hair. “Anyways, do you think we could have a sleepover up here? Maybe watch a couple of cartoons on the ol’ TV and cuddle a little bit?”

“Sounds like a great idea. As long as we put our clothes back on and dispose of the evidence from this rendezvous before we fall asleep. You know, so mom and dad never ever find out we had seriously illegal sex in the very sacred structure that dad built for us when we were little?”

“Ha, _yeah_ …”

“I’ll get the blankets and pajamas. You’re on snack duty,” he said, zipping his pants back up.

“Yes! I _love_ snack duty!” she replied excitedly as she gathered her clothes. “I’ll get the mallow whip and popcorn!”

Long story short, there wasn’t much on television in the way of cartoons that night. But they ended up having the time of their lives, regardless. Because when you have a treehouse with a television, a giant stack of throw pillows, and fairy lights, why would you ever have a bad time?


End file.
